1990s US SOF Pro-Tec Helmet HALO setup: The Pro-Tec helmet has bayonet lugs attached to the sides for an oxygen mask. There is also a boom mic mount base located at the bottom left for communication setup. The front of the helmet has a block made by duct tape to secure the skydiving goggles from sliding off when it is over the helmet. Pictures also feature a Scott MBU-12/P oxygen mask and a Kroop’s skydiving boogie goggles.